System of control



A. H. CANDEE.

SYSTEM OF CONTROL.

APPLICATION FILED JUNE 15, 1917.

Patented Feb. 1, 1921.

5 e 5 Z we Td 5 N H E E4 w w a w 0 E I. r m d N m wmm u ww mm i n w WATTORNEY UNITED STATES PATENT I OFFICE.

ANDREW H. CANDEE, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTING-HOUSE ELECTRIC & MANUFACTURING COMIANY, A CORPORATION OF PENN- BYLVANIA.

Be it known that 1, ANDREW H; OArInnn, a citizen of the United States,and a resident of Pittsburgh, in the count of'Allegheny and State ofPennsylvania, ave invented a new and useful 1m rovement inSystems ofControl, of which t e following is aspecification.

My invention relates to systems of control and particularly to systemsof control for electric railway vehicles.

One object of my invention is to provide a system of the above indicatedcharacter that shall open the circuit of a motor under predeterminedconditions and prevent the operation of the motor until themotor-governing controller is-returned to the oii position.

Another object of my invention is to provide a system of control for anelectric motor that shall be provided with a line switch for closing themotor circuit and means for pre venting the operation of the line switchunder predetermined conditions. I

Another object of my invention is to provide a control systemof theabove indicated character that shall be provided with a switch forclosing the motor circuit, a controller for governing theoperation ofthe motor, an overload-trip switch and a plurality of interlock switchesfor releasing the line switch under predetermined conditions,

- and means for preventing the operation of the line switch until thecontroller is returned to the oif posit10n, in case the line switch isreleased when the controller is 1n 7 an operative position.

In electric-railway-vehicle-control systems now m service are severallyembod1ed means for energizing a line switch for completing a circuitthrough a motor when the motorgoverning controller is moved to its firstoperative position and means, as, for example, door-interlock switches.or a slip segment of well known type, for releaslng the line switchunder predetermined conditions when the controller is in an operativeposition. Howeven'in each ofthe systems of the type above indicated, thehue switch is operated to complete the motor circmt momentarily when thecontroller is returned through the first operative posltion and thusgives the car an unnecessary jolt.

ln-a system embody ng my 1nvent1on, a

Specification of Letters Patent.

' by means of'a line switch Patented Feb. 1, 1921-.

1917. Serial No. 174,933.

line switch is o erated to complete the motor circuit when t econtroller is in the first operative position but means is provided, incase the line switch is released when the controller is in an operativeposition, for preventmg the operation of the line switch again until thecontrolleris returned to the ofi position and thus preventing theunnecessary jolt to the vehicle that is encountered in systems now inservice, when the controller is returned to the first operativeposition.

The single figure of the accompanying drawing is a diagrammatic'view ofa control system embodying my invention.

In the accompanying drawing, a motor 1, embodying an armature 2 and afield winding 3, is adapted to be connected across a supply circuitcomprising a trolley conductor 4: and a ground-return conductor 5 6 anda controller 7. I

The controller 7 embodies a contact segment 8 for engaging contact finers 9 and control circuits to the trolley conductor 4,

contact segment 11, which is adapted to engage the contact fingers 1213, 14, 15 and 16 for excluding resistors ltl, R2 and R3 from thecircuit of the motor 1, and a slipcontact segment 17 which is adapted toengage the contact fingers 18 and 19, when the controller is moved ina'forward direction, for a, purpose to be described later.

The slip-contact segment 17 is mounted upon a slip ring 20 that isfrictionally attached to; the controller 7 and is provided with twoprojections 21 and 22 which are respectively adapted to engage astationary pin 23 when the controller is moved in a forward and in areverse direction. Thus,

when the controller is moved in a .forward' ages the direction, theprojection 21 en pin 23, and'the contact segmentl is maintained inengagement'with the contact fingers 18 and 19, and, when the controlleris moved in a reverse direction a predetermined distance, the projection22 engages the pin 23, and the contact segment 17 is disengaged fromcontact with the fingers 18 and 19.

The line switch 6 is provided with an operating coil 24 and twointerlock switcheq 25 and 26, for a purpose to be described later.

v An auxiliary switch 27, which is adapted to bridge contact terminals28 when in an operative position and to bridge con-- line switch untilthe controller is returned to the off position in case the line switchis released when the controller is in an operative position.

Two door interlock switches 30 and 31 and an overload-trip switch 32 areprovided for deenergizing the coil '24 of the line switch in case a doorof the vehicle is opened, or in case an excessive current passes throughthe motor.- The coil 24 of the line switch 6 is adapted to be connectedacross a portion of a resistor 33, which is connected between thesupply-circuit conductors, and the coil of the auxiliary switch 27 isadapted to be connected across the supply circuit through a resistor 34.

Assuming the various control apparatus to be in the position illustratedin the'drawing, the motor 1, may be connected across the supply circuitwhen the master controller 7 is moved to position a. In position a ofthe controller 7, acircuit is completed from the trolley. conductor 4through the contact fingers 9 and 10-which are bridged by the contactsegment 8a portion of resistor 33, overload-trip switch 32, coil 24 ofthe line switch, contact terminals 29which are bridged by the movablemember of switch 27-contact fingers 18 and 19-which are bridged by theslip segment 17--and interlock switches 30 and 31 to the ground-.

return conductor 5. Thus, the line switch 6 is operated to complete acircuit from the trolley conductor 4 through the line switch 6, contactfingers 12 and 13which are brid ed by the contact segment 11-resistorsR1, 2 and R3, coil of the overload-trip switch 32 and motor 1 totheground-return conductor 5.

28. A holding circuit for the line switch 6' is completed through theinterlock switch 25 previous to the opening of the energizing circuittherefor, by the operating of the auxiliary switch 27-.

' i In positions b, c d of the controller 7,

the resistors R1, R2 and R3 are successively excluded from the circuitof the motor 1.

In case the circuit for the coil 24 of the line switch 6 isbroken bymeans of the slip segment 17 or the overload-trip switch 32, or the doorinterlock switches 30 and 31, the line switch is released and thecircuit of the motor 1 is broken. The holding circuit for the coil oftheauxiliary switch 27 fromthe trolley conductor 4 through the contactfingers 9 and 10which are bridged by the contact segment 8resistor 34,contact terminals 28-which are bridged by the relay 27-aiid the coil ofthe relay 27 to the ground-return conductor 5 is maintained closed untilthe controller 7' is returned to the off position to disconnect thecontact segment 8 from the contact fingers 9 and 10.

Inasmuch as the line switch 6 cannot be operated while the auxiliaryswitch 27 is in an operative position, it is apparent that, if thelineswitch is released when the-controller is in an operative position, itis impossible to operate the lineswitch and complete the motor circuituntil the controller is returned to the off position.

. Modifications inthe system and arrange ment and location of parts maybe made within the spirit and scope of my invention and suchmodifications are intended to be covered ,by the appended claims.

- I claim as my invention:

1. In a system of c ntrol, the combination with a motor'and a ontrollerfor governing the operation of'the motor, of means for breaking thecircuit of the motor under predetermined'conditions when the controlleris in an operative position, and a switch energized in all operativepositions of said controller for preventing. the reclosure of the motorcircuit ulntil the controller is returned to the off position.

2. In a system of control for an electric vehicle, the combination witha motor, and a controller for governing the operation'of the motor, ofmeans for openin the motor or the controller is moved in a reversedirection a slight amount from an operative position, and means forreventing the reclosing of the motor circuit until the controller ismoved to the ofi position.

3. In a system of control foran electric Vehicle, the combination with amotor. a line switch for completing the motor circuit, and a controllerfor governing the operation of the motor, of an auxiliary switch forefiecting the operation of the line switch to complete the motor circuitwhen the controller is in the first operative osition and forpreventing, when energize the operation of the line switch when the samehas been released until the controller is returned to the ofi position.

4. In a. systemof control, the combinecircuit in case a door of thevehic e is opened troller for governing the operation of the" motor, ofmeans for releasing the line switch, under predetermined conditions, to

open the motor circuit when the controller is in an operative position,and an auxiliary switch energizedin all operative positions of thecontroller for preventing the operation of the line switch until thecontroller is moved to the off position.

5. In a system of control, the combination with a motor, anelectrically-operated line switch for completing the circuit of themotor, and a controller for governing the operation of the motor, ofmeans comprising interlock switches for deenergizing the coil of theline switch, under predetermined conditions, when the controller is inan operative position, and an auxiliary switch initially closed by theline switch and adapted to prevent, when energized, the operation of theline switch until the controller is moved through the off position.

6. In a system of control, the combination with a motor, anelectrically-operated line switch for completing the circuit of themotor, and a controller for Q'OVQTIIIDQ' the operation of the motor, ofan overload-trip switch inserted in the circuit of the operating coilfor said line switch and having an energizing coil in the motor circuit,and means for. preventing, when energized, the operation of the lineswitch until the controller is returned to the off position in case theline switch is released by the overload: trip switch when the controlleris in an operative position.

7. In a system of control, the combination with a dynamo-electricmachine and a controller for governing the operation thereof, of meansfor closing the circuit thereof, and initially inoperative means topermit the action of the first means in the firstoperative position ofthe controller and thereafter operative to prevent repetition of suchaction after the opening of the first means until the machine circuitsresume their original condition.

8. In a system of control, the combination with a dynamo-electricmachine and a controller therefor, of means for closing the machinecircuit, and an initially inoperative switching device to permit theaction of said means in the first operative positionof the controllerand thereafter operative to prevent repetition of such action after theopening of said means whenever the controller occupies an operativeposition.

9. In a system of control, the combination with a dynamo-electricmachine and a controller therefor, of a switch for closing the machinecircuit, and a relay device hav ing contact members in theswitch-controlling circuit and having an actuating coil energized by theclosure of said switch, and an additional energizing circuit for saiddevice.

10. In a system of control, the combination with a dynamo-electricmachine. and a controller therefor, of a switch for closing the machinecircuit, and a relay device having contact members in theswitch-controlling circuit and having an actuating coil energized by theclosure of said switch, and a holding circuit for said device energizedonly upon the closure thereof under operating conditions.

-11. In a system of control, the combination with a dynamo-electricmachine and a controller therefor, of a switch for closing the 1 machinecircuit, means dependent upon the current traversing the machine forreleasing said switch, and an initially inoperative relay device topermit the closure of said switch in the first operative position of thecontroller and thereafter operative to prevent re-closure after theoperation of said means until the controller occupies a predeterminedposition.

In testimony whereof, I have hereunto subscribed my name this 28th dayof May,

ANDREW H. CANDEE.

